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A light is to be placed atop a pole of height h feet to illuminate a busy traffic circle, which has a radius of 40 ft. The intensity of illumination I at any point P on the circle is directly proportional to the cosine of the angle θ (see the figure) and inversely proportional to the square of the distance d from the source.

  1. How tall should the light pole be to maximize I?
  2.  

Chapter 3, Problem 67RE, A light is to be placed atop a pole of height h feet to illuminate a busy traffic circle, which has

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B. Haranadh Kumar
B. Haranadh KumarLv10
7 Dec 2020

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Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

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